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Community Member

DNS Issue.?

Hi All,

where do I begin to search a problem with some pages loading, but others not in a browser on a LAN. Couldn't ping the specific sites either, then, 5mins later, all was well. Messenger wouldn't connect either, then was ok. Is this DSN specific.?


Example ping result for 1 site that wouldn't load:

[root@localhost ~]# ping

ping: unknown host


Unknown host constitutes DNS resolving issues, yes..? I restarted the router, with no initial improvement. Checked on another PC(laptop) on the same subnet with same results. This is my home LAN, nothing Cisco specific, but, thought this is the place where knowledgable network people hang. Sorry if it's inappropriate. Cheers.


Community Member

Re: DNS Issue.?

DNS Troubleshooting

Start with "your" DNS Server Internal or External

Ping DNS Server IP Address

NSLOOKUP DNS Server IP Address

Is the Host looking at this DNS Service?

If the IP and Name resolution is good then it could be DNS Cache on DNS Service, Traffic on DNS Service, Configuration of DNS Service (especially if new)

Not being able to ping the IP address of the target host definitely is NOT a DNS issue. Traffic to the site external or internal may be the cause of the ping timing out.

Hope this helps

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